Thermoplastic adhesives, otherwise known as “hot melt” adhesives have been widely used in industry for adhering many types of products. Hot melt adhesive dispensing systems generally include a dispenser coupled with one or more dispensing guns, heated hoses fluidly connected to the guns, and a melting unit for melting and supplying heated liquid adhesive to the guns through the heated hoses. The melting units of conventional hot melt adhesive systems typically include a tank, a heater, a pump, a pump manifold, and a controller. The heater is generally located in a base of the tank for melting and heating adhesive material received into the tank in solid or semi-solid form. The pump manifold has an inlet connected to the tank and has multiple outlet ports adapted for connection to the heated hoses.
After the adhesive material is melted and heated in the tank, a pump operatively coupled to the tank and the pump manifold pumps liquid adhesive from the tank, through the pump manifold and heated hoses to the dispensing guns. Typically, the guns are connected to their own manifold. The controller controls the power supplied to the tank heater and heated hoses to maintain the liquid adhesive at an appropriate viscosity and temperature, depending on the application. The controller is also used to control many other operations of the system.
Before an adhesive dispensing operation can begin, the operator must ensure that the system parameters are set to values that are appropriate for the particular adhesive being used, as well as for the application needs. As some examples, system conditions such as adhesive application temperature, set back temperature, and over-temperature conditions should be set in the controller. If the system parameters are incorrectly set, various problems can arise such as overheating and charring of the adhesive, or underheating of the adhesive which could result in operational problems and adhesive bonding problems. Various other conditions may need to be set to establish a proper dispensing cycle. For example, there will be a delay time between when the system is turned on and the time that actual dispensing can take place.
A need therefore exists for a hot melt adhesive dispensing system having the ability to better ensure that system parameters are properly set in the controller. It would also be desirable to enable an operator to more easily and positively establish system conditions appropriate to the adhesive being processed, and efficiently utilize information related to system operation.